def get_connection(self, host):
# First try to take one out of the pool for this host
(server, instance) = host
port = self.ports[host]
connectionPool = self.connections[host]
try:
return connectionPool.pop()
except KeyError:
pass #nothing left in the pool, gotta make a new connection
log.cache("CarbonLink creating a new socket for %s" % str(host))
connection = socket.socket()
connection.settimeout(self.timeout)
try:
connection.connect( (server, port) )
except:
self.last_failure[host] = time.time()
raise
else:
connection.setsockopt( socket.SOL_SOCKET, socket.SO_KEEPALIVE, 1 )
return connection
def renderView(request):
start = time()
(graphOptions, requestOptions) = parseOptions(request)
useCache = 'noCache' not in requestOptions
cacheTimeout = requestOptions['cacheTimeout']
requestContext = {
'startTime' : requestOptions['startTime'],
'endTime' : requestOptions['endTime'],
'localOnly' : requestOptions['localOnly'],
'data' : []
}
data = requestContext['data']
# First we check the request cache
if useCache:
requestKey = hashRequest(request)
cachedResponse = cache.get(requestKey)
if cachedResponse:
log.cache('Request-Cache hit [%s]' % requestKey)
log.rendering('Returned cached response in %.6f' % (time() - start))
return cachedResponse
else:
log.cache('Request-Cache miss [%s]' % requestKey)
# Now we prepare the requested data
if requestOptions['graphType'] == 'pie':
for target in requestOptions['targets']:
if target.find(':') >= 0:
try:
name,value = target.split(':',1)
value = float(value)
except:
raise ValueError, "Invalid target '%s'" % target
data.append( (name,value) )
else:
seriesList = evaluateTarget(requestContext, target)
for series in seriesList:
func = PieFunctions[requestOptions['pieMode']]
data.append( (series.name, func(requestContext, series) or 0 ))
elif requestOptions['graphType'] == 'line':
# Let's see if at least our data is cached
if useCache:
targets = requestOptions['targets']
startTime = requestOptions['startTime']
endTime = requestOptions['endTime']
dataKey = hashData(targets, startTime, endTime)
cachedData = cache.get(dataKey)
if cachedData:
log.cache("Data-Cache hit [%s]" % dataKey)
else:
log.cache("Data-Cache miss [%s]" % dataKey)
else:
cachedData = None
if cachedData is not None:
requestContext['data'] = data = cachedData
else: # Have to actually retrieve the data now
for target in requestOptions['targets']:
t = time()
seriesList = evaluateTarget(requestContext, target)
log.rendering("Retrieval of %s took %.6f" % (target, time() - t))
data.extend(seriesList)
if useCache:
cache.set(dataKey, data, cacheTimeout)
format = requestOptions.get('format')
if format == 'csv':
response = HttpResponse(mimetype='text/csv')
writer = csv.writer(response, dialect='excel')
for series in data:
for i, value in enumerate(series):
timestamp = datetime.fromtimestamp(series.start + (i * series.step), requestOptions['tzinfo'])
writer.writerow((series.name, timestamp.strftime("%Y-%m-%d %H:%M:%S"), value))
return response
if format == 'json':
series_data = []
for series in data:
timestamps = range(series.start, series.end, series.step)
datapoints = zip(series, timestamps)
series_data.append( dict(target=series.name, datapoints=datapoints) )
if 'jsonp' in requestOptions:
response = HttpResponse(
content="%s(%s)" % (requestOptions['jsonp'], json.dumps(series_data)),
mimetype='text/javascript')
else:
response = HttpResponse(content=json.dumps(series_data), mimetype='application/json')
response['Pragma'] = 'no-cache'
response['Cache-Control'] = 'no-cache'
return response
if format == 'raw':
response = HttpResponse(mimetype='text/plain')
for series in data:
response.write( "%s,%d,%d,%d|" % (series.name, series.start, series.end, series.step) )
response.write( ','.join(map(str,series)) )
response.write('\n')
log.rendering('Total rawData rendering time %.6f' % (time() - start))
return response
if format == 'svg':
graphOptions['outputFormat'] = 'svg'
if format == 'pickle':
response = HttpResponse(mimetype='application/pickle')
seriesInfo = [series.getInfo() for series in data]
pickle.dump(seriesInfo, response, protocol=-1)
log.rendering('Total pickle rendering time %.6f' % (time() - start))
return response
# We've got the data, now to render it
graphOptions['data'] = data
if settings.REMOTE_RENDERING: # Rendering on other machines is faster in some situations
image = delegateRendering(requestOptions['graphType'], graphOptions)
else:
image = doImageRender(requestOptions['graphClass'], graphOptions)
useSVG = graphOptions.get('outputFormat') == 'svg'
if useSVG and 'jsonp' in requestOptions:
response = HttpResponse(
content="%s(%s)" % (requestOptions['jsonp'], json.dumps(image)),
mimetype='text/javascript')
else:
response = buildResponse(image, useSVG and 'image/svg+xml' or 'image/png')
if useCache:
cache.set(requestKey, response, cacheTimeout)
log.rendering('Total rendering time %.6f seconds' % (time() - start))
return response
def set_metadata(self, metric, key, value):
request = dict(type='set-metadata', metric=metric, key=key, value=value)
results = self.send_request(request)
log.cache("CarbonLink set-metadata request received for %s:%s" % (metric, key))
return results
def query(self, metric):
request = dict(type='cache-query', metric=metric)
results = self.send_request(request)
log.cache("CarbonLink cache-query request for %s returned %d datapoints" % (metric, len(results)))
return results['datapoints']